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Climate and topography regulate the spatial pattern of soil salinization and its effects on shrub community structure in Northwest China

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Journal of Arid Land 2024年第7期16卷 925-942页

作者： du Lan TIAN Shengchuan ZHAO Nan ZHANG bin MU Xiaohan TANG Lisong ZHENG Xinjun LI Yan State Key Laboratory of desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Fukang Station of desert Ecology Chinese Academy of SciencesFukang 831505China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China

Soil salinization may affect biodiversity and species composition,leading to changes in the plant community ***,few studies have explored the spatial pattern of soil salinization and its effects on shrub community structure at the ecosystem ***,we conducted a transect sampling of desert shrublands in Northwest China during the growing season(June–September)in *** salinization(both the degree and type),shrub community structure(e.g.,shrub density and height),and biodiversity parameters(e.g.,Simpson diversity,Margalf abundance,Shannon-Wiener diversity,and Pielou evenness indices)were used to assess the effects of soil salinization on shrub community *** results showed that the primary degree of soil salinization in the study area was light salinization,with the area proportion of 69.8%.Whereas the main type of soil salinization was characterized as sulfate saline soil,also accounting for 69.8%of the total ***,there was a significant reduction in the degree of soil salinization and a shift in the type of soil salinization from chloride saline soil to sulfate saline soil,with an increase in *** mean annual precipitation(MAP),mean annual evapotranspiration(MAE),elevation,and slope significantly contributed to soil salinization and its geochemical *** soil salinization intensified,shrub community structure displayed increased diversity and evenness,as indicated by the increases in the Simpson diversity,Shannon-Wiener diversity,and Pielou evenness ***,the succulent stems and leaves of Chenopodiaceae and Tamaricaceae exhibited clear advantages under these ***,regional climate and topography,such as MAP,MAE,and elevation,had greater effects on the distribution of shrub plants than soil *** results provide a reference for the origin and pattern of soil salinization in drylands and their effects on the community structure of halophyte shrub species.

关键词： soil salinization halophytes shrubland climate change biodiversity drylands Northwest China

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Evaluating soil acidification risk and its effects on biodiversity–ecosystem multifunctionality relationships in the drylands of China

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Forest Ecosystems 2024年第2期11卷 162-171页

作者： Lan du Shengchuan Tian Nan Zhao bin Zhang Xiaohan Mu Lisong Tang Xinjun Zheng Yan Li State Key Laboratory of desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi830011XinjiangChina University of Chinese Academy of Sciences Beijing100049China Fukang Station of desert Ecology Chinese Academy of SciencesFukang831505XinjiangChina State Key Laboratory of Subtropical Silviculture Zhejiang A and F UniversityHangzhou311300ZhejiangChina

Background:Soil acidifcationn caused by anthropogenic activities may aft soil biochemical cydling,bidiversity,productivity,and multiple eosystem-related functions in ***,to date,such information is lacking to support this *** Based on a transect survey of 78 naturally assembled shrub communities,we caloulated acid deposition flux in Northwest China and evaluated its likely ecological ffets by testing three altemnative hypotheses,namely:.nidche complementarity,mass ratio,and vegetation quantity hypotheses Rao's quadratic entopy and community-weighted mean traits were employed to represent the complementary aspect of niche complementarity and mass ratio effects,***:We observed that in the past four decades,the concentrations of exchangeable base cations in soil in Northwest China have decreased significantly to the extent of having faced the risk of depletion,whereas changes in the calium carbonate content and pH of soil were not *** deposition primani ly increased the aboweground biomass and shrub density in shrublands but had no sigmificant effect on shrub richness and ecasystem multifunctionality(EMF),indicating that acid deposition had positive but weak ecological effects on dryland *** wd ghted mean of functional traits(representing the mass ratio hypothesis)correlated negatively with EMF,whereas both Rao's quadratic entropy(representing the niche complementarity hypothesis)and aboveground biomass(representing the vegetation quantity hypothesis)correlated positively but insignifcantly with *** biodiversity-EMF relationships highlight the fragility and instability of drylands relative to forest ***:The findings from this study serve as important reference points to understand the ris of soil acidification in arid regions and its impacts on biodiversity-EMF relationships.

关键词： Soil acidification risk Biodiversity Ecosystem multifunctionality Niche complementarity hypothesis Mass ratio hypothesis Vegetation quantity hypothesis

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One-pot Synthesis of MoO_(3)/PI Composite with Enhanced Photocatalytic Performance for Oxidative Coupling of Amines to Imines

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 57-71页

作者： Zhao Wenjie du Chengxin Song Yu Zhou Yafen Wang Qing Zhou Limei Xu bin Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province College of Chemistry and Chemical EngineeringChina West Normal UniversityNanchongChina Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education Sichuan University of Science&EngineeringZigongChina

Organic-inorganic MoO_(3)/PI(MoPI)composites were prepared using a simple one-pot thermal copolymerization *** resulting composites exhibited enhanced photocatalytic activity for the selective oxidation of benzylamine to N-benzylidene benzylamine(N-BDBA)in ambient air under simulated solar light irradiation compared to pristine MoO_(3) or polyimide(PI).In particular,the MoPI composite with a 0.3:1 molar ratio of Mo to melamine,referred to as MoPI-0.3,demonstrated the best performance in the photo-oxidation of benzylamine,achieving a benzylamine conversion of 95%with a N-BDBA selectivity exceeding 99%after 3 h *** enhanced photocatalytic activity of the MoPI-0.3 catalyst was attributed to the formation of a direct Z-scheme heterojunction between MoO_(3) and PI,facilitating more efficient separation of the photoinduced electrons and ***,the MoPI-0.3 composite maintained considerably high activity over four consecutive cycles,highlighting its good stability and ***,the MoPI-0.3 composite could photo-oxidize benzylamine derivatives and heterocyclic amines to their corresponding imines,demonstrating the universal applicability of this composite catalyst.

关键词： MoO3/PI composite photocatalysis amine oxidation imine

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中国省域创新产出的空间格局与空间溢出效应研究

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软科学 2016年第10期30卷 6-10,30页

作者：杨凡杜德斌林晓华东师范大学科技创新与发展战略研究中心上海200062

以1999~2013年中国31个省市为基本时空单元,应用探索性和确认性空间数据分析方法,对中国省域创新产出的空间格局与空间溢出效应进行分析。研究发现：省域创新产出的高值区形成以沿海经济带与长江经济带为轴的“T型”结构;地理邻近是省... 详细信息

以1999~2013年中国31个省市为基本时空单元,应用探索性和确认性空间数据分析方法,对中国省域创新产出的空间格局与空间溢出效应进行分析。研究发现：省域创新产出的高值区形成以沿海经济带与长江经济带为轴的“T型”结构;地理邻近是省域创新产出集聚的主要空间关联模式,形成京津的虹吸、上海的扩散和粤辽的弱辐射三类区域效应;省域创新产出增长率存在正向空间溢出,但若不平衡创新资源配置,省域创新产出仍将陷入持续空间分异;创新产出、人力资本和资金资本均存在正向空间溢出,经济发展水平存在负向空间溢出,创新基础设施的空间溢出不显著,各创新投入变量空间溢出的传导机制不同。

关键词：创新产出空间格局空间溢出空间计量

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1996-2012年中国科技创新重心的空间演变及其影响因素分析:基于省域数据的研究

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华东师范大学学报（自然科学版） 2016年第3期 115-124页

作者：李恒杜德斌肖刚华东师范大学科技创新与发展战略研究中心上海200062 华东师范大学城市与区域科学学院上海200241

科技创新能力对区域社会经济发展起到日益重要的作用,在已有研究基础上,将重心模型引入到我国区域科技创新能力差异演变的研究当中,计算了1996-2012年我国科技创新重心并分析了其演变特征,通过比较分析和定量研究总结了驱动我国科技创... 详细信息

科技创新能力对区域社会经济发展起到日益重要的作用,在已有研究基础上,将重心模型引入到我国区域科技创新能力差异演变的研究当中,计算了1996-2012年我国科技创新重心并分析了其演变特征,通过比较分析和定量研究总结了驱动我国科技创新重心演变的主要因素.研究结果表明:我国科技创新重心16年来快速向东南方向移动,逐渐偏离我国几何中心;我国科技创新重心与高技术产业重心、经济重心和研发投入重心具有较强的相关性;经济结构与增长方式、科技资源的空间集聚、科技创新环境是驱动我国科技创新重心移动的主要因素.

关键词：科技创新能力科技创新重心区域差异比较分析驱动机制

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区域知识创新系统中科技创新与高等教育的融合关系研究——基于长三角城市群的案例研究

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上海经济研究 2015年第5期27卷 86-94页

作者：李恒杜德斌肖刚华东师范大学科技创新与发展战略研究中心 200241

构建科技创新与高等教育融合度系统评价指标体系,通过融合度分析模型综合评价长三角地区城市科技创新与高等教育之间的交互融合关系。研究发现:从时间来看,随着研究期内长三角城市科技创新能力和高等教育水平逐年提升,长三角城市科技创... 详细信息

构建科技创新与高等教育融合度系统评价指标体系,通过融合度分析模型综合评价长三角地区城市科技创新与高等教育之间的交互融合关系。研究发现:从时间来看,随着研究期内长三角城市科技创新能力和高等教育水平逐年提升,长三角城市科技创新与高等教育之间的融合度也不断的提升,但是仍然处于融合度较低的关系失调阶段。从空间来看,长三角各城市的科技创新与高等教育融合度主要分布在较高融合度、较低融合度和低融合度三个阶段,高融合度阶段没有城市分布,大部分城市尚处于融合度差的阶段,不断提升这些城市的科教融合水平对于推动区域社会经济的可持续发展十分必要。

关键词：长三角城市科技创新高等教育融合度

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Response characteristics of PWR primary circuit under SBLOCAs considering steam bypass discharging

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Nuclear Science and Techniques 2024年第6期35卷 189-201页

作者： Shuai Yang Xiang-bin Li Yu-Sheng Liu Jia-Ning Xu de-Chen Zhang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy Beijing 102206China Nuclear and Radiation Safety Center MEPBeijing 100084China

Small-break superposed station blackout(SBO)accidents are the basic design accidents of nuclear power *** the condition of a small break in the cold leg,SBO further increases the severity of the accident,and the steam bypass discharg-ing system(GCT)in the second circuit can play an important role in guaranteeing core *** explore the influence of the GCT on the thermal-hydraulic characteristics of the primary circuit,RELAP5 software was used to establish a numerical model based on a typical pressurized water reactor nuclear power *** different small breaks in the cold-leg super-posed SBO were selected,and the impact of the GCT operation on the transient response characteristics of the primary and secondary circuit systems was *** results show that the GCT plays an indispensable role in core heat removal during an accident;otherwise,core safety cannot be *** GCT was used in conjunction with the primary safety injection system during the placement *** the break diameter was greater than a certain critical value,the core cooling rate could not be guaranteed to be less than 100 K/h;however,the core remained in a safe state.

关键词： Steam bypass discharging Pressurized water reactor SBLOCA Numerical simulation

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Multi-endpoint assays reveal more severe toxicity induced by chloraminated effluent organic matter than chloraminated natural organic matter

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Journal of Environmental Sciences 2024年第1期135卷 310-317页

作者： Hai-Yan Wang de-Xiu Wu Ye du Xiao-Tong Lv Qian-Yuan Wu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environmental Protection Key Laboratory of Microorganism Application and Risk Control Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China College of Architecture and Environment Sichuan UniversityChengdu 610000China

Disinfection by chloramination produces toxic byproducts and the difference in toxicity of reclaimed and drinking water treated by chloramination remains *** study investigated cytotoxic effects at the same concentrations of dissolved organic matter and showed that chloraminated effluent organic matter(EfOM)induced 1.7 times higher cytotoxicity than chloraminated natural organic matter(NOM)applied to simulate drinking *** EfOM induced more reactive nitrogen species than chloraminated NOM,and chloraminated EfOM and NOM induced similar and higher levels of reactive oxygen species than the negative control,***,intracellular macromolecule damage indicated by DNA/RNA damage marker 8–hydroxy-(deoxy)guanosine and the intracellular protein carbonyl concentration induced by chloraminated EfOM was higher and slightly more than that induced by chloraminated NOM,*** data were consistent with the effects on cell physiological *** cycle arrest mainly occurred in G2 phase by chloraminated EfOM and *** apoptotic cells,which could return to normal,increased upon exposure to high concentrations of chloraminated EfOM and ***,necrotic cells were significantly increased from 0.5%to 2.5%when the concentration increased from 20-to 60-fold chloraminated EfOM,but were not obviously changed by chloraminated *** results indicated that the comprehensive intracellular changes induced by toxic substances in chloraminated EfOM were more irreversible and induced more cell death than chloraminated NOM.

关键词： Cytotoxicity Intracellular active nitrogen/oxygen Intracellular oxidative damage Cell necrosis Reclaimed water

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品牌契合、消费者品牌价值创造与品牌价值——基于企业微信公众号的分析

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江西财经大学学报 2018年第3期 40-49页

作者：郭爱云杜德斌北京林业大学经济管理学院北京100083 北京农学院经济管理学院北京102206

当前微信公众号已成为企业品牌管理的新型平台。从理论上分析了企业微信公众号中消费者品牌契合与品牌价值间的关系。根据对三只松鼠微信公众号用户的调查数据,经实证检验发现,消费者从公众号中获得的体验价值促进了品牌契合的形成,对... 详细信息

当前微信公众号已成为企业品牌管理的新型平台。从理论上分析了企业微信公众号中消费者品牌契合与品牌价值间的关系。根据对三只松鼠微信公众号用户的调查数据,经实证检验发现,消费者从公众号中获得的体验价值促进了品牌契合的形成,对消费者品牌价值创造和品牌价值提升具有积极影响;消费者品牌价值创造在品牌契合与品牌价值之间起中介作用,社区支持感起正向调节作用。企业要重视公众号对品牌价值的积极影响,提高消费者的品牌契合;增强消费者的社区支持感,强化品牌契合对消费者品牌价值创造的积极效应。

关键词：企业微信公众号品牌契合消费者品牌价值创造品牌价值社区支持感

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中国R&D投资环境的竞争力评价

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研究与发展管理 2006年第2期18卷 85-91页

作者：楚天骄杜德斌中国浦东干部学院上海201204 华东师范大学中国现代城市研究中心上海200062

构建了指标体系对世界48个国家(地区)R&D投资环境的竞争力进行评价.结果显示,中国R&D投资环境的竞争力处于中等水平,在吸引跨国公司知识利用型R&D投资方面具有较强的竞争力,但由于基础设施条件和政策环境的制约,在吸引跨国公司知识生产... 详细信息

构建了指标体系对世界48个国家(地区)R&D投资环境的竞争力进行评价.结果显示,中国R&D投资环境的竞争力处于中等水平,在吸引跨国公司知识利用型R&D投资方面具有较强的竞争力,但由于基础设施条件和政策环境的制约,在吸引跨国公司知识生产型R&D投资方面竞争力不强.

关键词： R&D 投资环境竞争力

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